By now most have probably read of the terrible level crossing accident in New York.

This article in the New York Times gives more details than any other account I've seen. In particular, it includes the eye witness account of the driver of the car behind the one hit by the train. The actions of the deceased motorist beggar belief.

I've put this in 'Level Crossings' rather than 'Overseas' as this accident could happen anywhere there are level crossings protected by boom barriers. Given the circumstances of this case, it is possible that even remote supervision or occupancy detectors may not have prevented the accident.

Andrew Waugh wrote:Given the circumstances of this case, it is possible that even remote supervision or occupancy detectors may not have prevented the accident.

From the news article, it sounds as if the driver was inside the gates as they came down, with the barrier resting on her rear window - I would have thought that the gates would be visible on CCTV at least, meaning the car would also be visible. I'm not sure how far from the tracks OD systems scan.

Tragic indeed, but I would have thought such an accident could only happen here on an automatic half barrier (AHB) crossing (and did - at Ufton Nervet in 2004 - see recent post on that subject). Where full gates or barriers are controlled and supervised - either from an adjacent signalbox, by CCTV, or by Obstacle Detection - then the crossing must be proved clear before the protecting signals can be cleared. It doesn't sound as if that condition would have been met by any of our systems in the NY accident.

This was an AHB, although its position close to a light-controlled road junction would not be regarded as suitable for this type of crossing in the UK. I believe supervised crossings are extremely rare in North America.

The reason I raised the possibility that the accident *might* not have been prevented by obstacle detection or remote supervision was that it appears that the car may not have been initially foul of the line.

The road crosses the railway at an acute angle, and the booms are erected at right angles to the road, not parallel to the railway (as I am used to). The result is that there is a significant distance between the boom and the fouling point, and the report suggests that the car was initially sitting in this gap. The driver then drove the car forward into the path of the train.

I have no doubt that obstacle detection or remote supervision by CCTV would have detected the car if it was sitting squarely across the railway, or even significantly encroaching on the line. However, it is not clear that either approach would *always* detect a car that was sitting just outside the clearance area.

Behind this technical question is the real issue, and the cause of my despairing question.

It appears that the accident was turned into a tragedy by the mistake of the driver in driving forward into the path of the train. How can you stop people making such mistakes?

One solution is to grade separate (or close) every crossing. This might be practical in the UK, but it's not in the US (or Australia, for that matter).

The greatest risk is the deliberate placing of a car on the crossing.With advances made with CCTV technology the answer is to provide a small screen in a Driving cab which through GPS or whatever would trans mitt from a distance to the train automatically whats happening at the crossing.Where two crossing s are close together two screens in the cab would not be a problem or one screen could scan the crossings continuously as the train approached.The TFL already provide monitor screens on some of their lines.Rising Ramps as they have at car parks or larger ones as used at MOD sites placed on the approach to crossings could also be considered.

The speculation as to the trapped motorist's reaction seems to be based on the story of a single eye witness. He may well be right, but I would not be unduly surprised if a formal investigation produces a different conclusion.

The news report makes it clear that traffic on this road was heavier than normal as a diversionary route for a road accident at the next junction to the south, so the unfortunate motorist may have been unfamiliar with this particular junction. It sounds as though she stopped where she did because of traffic block backing from traffic lights for the main road. She may well have failed to appreciate that she was apparently clear of the loading gauge where she was, the second picture suggesting that the barriers came on to her front wing, contrary the witness comment. The chap behind her obviously expected her to reverse when the bells started, but as she may well have been aware of this obstacle behind her, it may not have been entirely unreasonable of her to go forwards in an attempt to extricate herself from her sudden problem.

If a technical solution is sought, some sort of interlinking of the traffic lights with the crossing must be one contender. It might not meet British practice, but may be acceptable in the US. Obstacle detection, CCTV etc are not the answer for an automatic crossing where the train cannot be stopped by signals.

I trust the investigation will also pursue the penetration of two passenger carriages by the third rail and the extent of fire. These seem more disconcerting to me than the cause of the accident.

Although a train may not be able to stop on a fast line the driver with advance viewing of the crossing could reduce speed considerably to lessen injuries to passengers and at a lower speed this would push the obstruction along the track and may prevent a derailment.The vehicle construction standards are not as stringent in the USA and this was old stock.They build their stock to be the lightest possible.

scarpa wrote:The greatest risk is the deliberate placing of a car on the crossing.With advances made with CCTV technology the answer is to provide a small screen in a Driving cab which through GPS or whatever would trans mitt from a distance to the train automatically whats happening at the crossing.

I dare say that, at least in the UK, there would be some dislike from drivers about this option - I seem to recall there's already been some upset over the amount of time spent looking at screens in ERTMS areas, for example.

No difficulty interlocking traffic lights with l.c.s in the UK in time past (Gloucester Barton St. for example) and probably none now. Certainly a fine (non-UK) example can be studied at WWW.railcam.nl as I have often reccomended.

scarpa wrote:The vehicle construction standards are not as stringent in the USA and this was old stock.They build their stock to be the lightest possible.

Apologies for going off-topic but: Really? I have always understood that the FRA structural standards are far higher than those applying in Europe, and the trains accordingly much heavier.

That's what our old friend Jersey-Mike used to say as well, accompanied by recommendations to stop trying to make our level crossings safer and build stronger trains instead...

That would be so, I believe there are 2 or 3 places in the US and Canada (Ottawa) where European DMUs have been introduced on the rule that freight trains can only run at night when there are no passenger services due to the lower standards of crash worthiness in Europe.

1. I would also wonder about traffic light co-ordination. Melbourne is a city with many level crossings, and traffic light co-ordination is part of the standard where cars can queue over the level crossing. (For those not familiar with the idea, the level crossing protection and the traffic light controller are connected. When a train is approaching the level crossing, a call is made on the traffic lights to cycle to a phase that permits traffic on the road to drain and allow any cars foul of the railway to clear.) However, it's possible that this was provided at the intersection concerned. The final report may consider this issue.

2. The accident damage. I would suspect that the third rail pierced the car's petrol tank, and then the body of the railway car. Unlucky. The concentrated load of the end of a rail in a collision is hard to protect against. This is one of the benefits of continuously welded rail - jointed rail frequently caused this type of damage in collisions. The problem here is that the third rail *has* to be broken at level crossings and the end is a natural danger. The UK third rail electrification would be a similar risk. Overhead electrification is much safer in this regard.

3. Structural strength. At the risk of going off topic, US structural strengths are significantly higher, even today. It's difficult to compare, as the various codes use different ways of measuring strength. A relatively recent book gives the following figures which I think are comparable.

For post 1999 US main line stock: underframe at draftgear stops in buff (collapse): 800,000 lbs; collision post (telescoping) at base: 500,000 lbs.

It would consequently appear that modern US stock will resist approximately twice the buffing force of European stock. Anti telescoping is more complex as the US measures just above the underframe, while European standards measure it about halfwaybetween the floor and the roof (where leverage is worst, and hence strength lowest). But it would appear that the US standards are still significantly higher, and the UK seems very low.